From mboxrd@z Thu Jan 1 00:00:00 1970 From: Vladimir Zapolskiy Subject: [PATCH v2 09/14] ravb: fix invalid context bug while changing link options by ethtool Date: Wed, 4 Jul 2018 11:14:51 +0300 Message-ID: <20180704081451.7482-5-vladimir_zapolskiy@mentor.com> References: <20180704081245.7395-1-vladimir_zapolskiy@mentor.com> Mime-Version: 1.0 Content-Type: text/plain Cc: Andrew Lunn , Geert Uytterhoeven , , To: Sergei Shtylyov , "David S . Miller" Return-path: Received: from relay1.mentorg.com ([192.94.38.131]:42843 "EHLO relay1.mentorg.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933918AbeGDIP3 (ORCPT ); Wed, 4 Jul 2018 04:15:29 -0400 In-Reply-To: <20180704081245.7395-1-vladimir_zapolskiy@mentor.com> Sender: netdev-owner@vger.kernel.org List-ID: The change fixes sleep in atomic context bug, which is encountered every time when link settings are changed by ethtool. Since commit 35b5f6b1a82b ("PHYLIB: Locking fixes for PHY I/O potentially sleeping") phy_start_aneg() function utilizes a mutex to serialize changes to phy state, however that helper function is called in atomic context under a grabbed spinlock, because phy_start_aneg() is called by phy_ethtool_ksettings_set() and by replaced phy_ethtool_sset() helpers from phylib. Now duplex mode setting is enforced in ravb_adjust_link() only, also now RX/TX is disabled when link is put down or modifications to E-MAC registers ECMR and GECMR are expected for both cases of checked and ignored link status pin state from E-MAC interrupt handler. Fixes: a0d2f20650e8 ("Renesas Ethernet AVB PTP clock driver") Signed-off-by: Vladimir Zapolskiy --- drivers/net/ethernet/renesas/ravb_main.c | 49 ++++++++---------------- 1 file changed, 15 insertions(+), 34 deletions(-) diff --git a/drivers/net/ethernet/renesas/ravb_main.c b/drivers/net/ethernet/renesas/ravb_main.c index e7d6d1b6e7d6..40266fe01186 100644 --- a/drivers/net/ethernet/renesas/ravb_main.c +++ b/drivers/net/ethernet/renesas/ravb_main.c @@ -980,6 +980,13 @@ static void ravb_adjust_link(struct net_device *ndev) struct ravb_private *priv = netdev_priv(ndev); struct phy_device *phydev = ndev->phydev; bool new_state = false; + unsigned long flags; + + spin_lock_irqsave(&priv->lock, flags); + + /* Disable TX and RX right over here, if E-MAC change is ignored */ + if (priv->no_avb_link) + ravb_rcv_snd_disable(ndev); if (phydev->link) { if (phydev->duplex != priv->duplex) { @@ -997,18 +1004,21 @@ static void ravb_adjust_link(struct net_device *ndev) ravb_modify(ndev, ECMR, ECMR_TXF, 0); new_state = true; priv->link = phydev->link; - if (priv->no_avb_link) - ravb_rcv_snd_enable(ndev); } } else if (priv->link) { new_state = true; priv->link = 0; priv->speed = 0; priv->duplex = -1; - if (priv->no_avb_link) - ravb_rcv_snd_disable(ndev); } + /* Enable TX and RX right over here, if E-MAC change is ignored */ + if (priv->no_avb_link && phydev->link) + ravb_rcv_snd_enable(ndev); + + mmiowb(); + spin_unlock_irqrestore(&priv->lock, flags); + if (new_state && netif_msg_link(priv)) phy_print_status(phydev); } @@ -1115,39 +1125,10 @@ static int ravb_get_link_ksettings(struct net_device *ndev, static int ravb_set_link_ksettings(struct net_device *ndev, const struct ethtool_link_ksettings *cmd) { - struct ravb_private *priv = netdev_priv(ndev); - unsigned long flags; - int error; - if (!ndev->phydev) return -ENODEV; - spin_lock_irqsave(&priv->lock, flags); - - /* Disable TX and RX */ - ravb_rcv_snd_disable(ndev); - - error = phy_ethtool_ksettings_set(ndev->phydev, cmd); - if (error) - goto error_exit; - - if (cmd->base.duplex == DUPLEX_FULL) - priv->duplex = 1; - else - priv->duplex = 0; - - ravb_set_duplex(ndev); - -error_exit: - mdelay(1); - - /* Enable TX and RX */ - ravb_rcv_snd_enable(ndev); - - mmiowb(); - spin_unlock_irqrestore(&priv->lock, flags); - - return error; + return phy_ethtool_ksettings_set(ndev->phydev, cmd); } static int ravb_nway_reset(struct net_device *ndev) -- 2.17.1